International climate negotiations have stalled in recent years, offering little hope that the world might keep global warming under 2 degrees Celsius by the end of the century. But the United Nations' existing commitment to universal sustainable energy access could get most of the way toward that goal.

U.N. Secretary-General Ban Ki-moon launched the "Sustainable Energy for All" (SE4ALL) initiative in 2011. The program's three goals were to ensure universal access to modern energy, double the share of global renewable energy and double the rate of improvement in energy efficiency by 2030.

If all three objectives were met and sustained, the likelihood of keeping global temperature rise below 2 degrees would be more than 66 percent, according to a study released today in the journal Nature Climate Change.

"Achievement of the three objectives would provide an important entry point into stringent climate protection," said Joeri Rogelj, a researcher at ETH Zurich and lead author of the study.

While the SE4ALL initiatives do not address climate change directly, sustainable energy access is a fundamental part of reducing greenhouse gas emissions as well as eradicating poverty. The global energy system, including transportation; buildings; industry; and electricity, heat and fuel production, accounts for 80 percent on human-caused carbon dioxide emissions.

If only the goal to double the share of renewable energy is met, researchers found the probability of keeping temperature rise below 2 degrees ranges from 40 to 90 percent -- which alone is not enough certainty to guarantee climate stability. If only the goal to double energy efficiency is met, the chances improve to between 60 and 90 percent.

The third goal, to reach universal modern energy access, seems at odds with reducing greenhouse gases because it implies bringing more energy sources online overall. But researchers found that universal energy access would actually have a negligible effect on the climate, since modern energy sources, including fossil fuels, are so much more efficient than traditional energy materials.

More access to energy could have clean results
"When we talk about universal energy access in our paper, we're speaking about the three billion or so people in the developing world (primarily in South Asia, Sub-Saharan Africa, and Southeast Asia), who don't have any access to electricity at all and/or who still burn firewood, charcoal, or dung on a daily basis in order to cook their food and heat their homes," wrote David McCollum, a researcher with the International Institute for Applied Systems Analysis, in an email.

"Those latter processes are so incredibly inefficient that if people can be provided access to modern cooking and heating devices (even fossil-powered ones, e.g., kerosene or [liquefied petroleum gas] cook stoves), which are much more efficient, the total effect on greenhouse gas emissions will, on balance, be pretty marginal," he said.

Achieving modern energy access for all can actually complement the aim to double energy efficiency by updating the overall energy system.

But the SE4ALL goals alone will not ensure that long-term climate targets are met without the implementation of other measures to rein in greenhouse gas emissions, the authors wrote. These measures could include binding global, national or regional agreements to limit carbon dioxide through a tax or cap-and-trade program.

"Sustainable Energy for All is a bottom-up program with mainly local effects," Rogelj said. "For the climate there should be a global solution that really caps global greenhouse gases."

At least in the interim, however, SE4ALL goals might stand a better chance of success. The authors calculated that the cost for achieving all SE4ALL goals amounts to increasing energy investments by 0.1 to 0.7 percent of global gross domestic product beyond the baseline scenario -- a feasible amount. Baseline energy investments, not accounting for any energy or climate goals, are expected to total $1,360 billion in 2030.

The greatest barrier to fulfilling the United Nations' sustainable energy initiative is the resistance to change entrenched in the political, social and technological aspects of the energy system, said McCollum.

"The barriers for clean energy technologies are many, and that industry is still in a fledgling state, at least compared to the fossil fuels industry, which is mature, large, and powerful," he said. "Consider this: global fossil fuel subsidies currently amount to some $400 billion per year. That amount of money would, by our calculations, go a long way in achieving the SE4All goals."